package leetcode.d_1_99;

public class P96 {
    public int numTrees(int n) {
        int[] dp = new int[n+1];
        dp[0] = 1;
        dp[1] = 1;
        for (int i=2; i<n+1; i++) {
            for (int j=1; j<=i; j++) {
                dp[i] += dp[j-1]*dp[i-j];
            }
        }
        return dp[n];
    }
}
